LMK01801: Skew on between CG1 and CG2

Oba

Part Number: LMK01801

Hello,

My customer is going to use LMK01801 with the below configuration.
CLKin0=100MHz
CG1: CLKout0~2=100MHz
CG2: CLKout4~6=50MHz (Div 2)

They they would like to know skew between CG1(CH0~2) and CG2(CH4~6).
I found some E2E posts related to the skew topic, but all posts didn't answer for this case.

Do you have any data?

Regards,
Oba

4 days ago

0 Michael Srinivasan 3 days ago

TI__Genius 10280 points

Oba-san,

The skew between outputs depends on the output formats that each CLKout is driving. See the attachment below for more information.

Thanks,

Michael

0 Oba 1 day ago in reply to Michael Srinivasan

TI__Genius 17515 points

Hello Michael,

The value on the table in the datasheet you mentioned shows only for the same divider case.
My customer would like to know different divider case.

Regards,
Oba

0 Michael Srinivasan 17 hours ago in reply to Oba

TI__Genius 10280 points

Oba-san,

We specify this value this way because we assume that the customer will be using the SYNC functionality offered by the device. Assuming that both output banks are phase aligned, the skew between outputs from different dividers is identically the same as it would be between outputs of the same divider that are not synchronized.

If the banks are not synchronized, then the skew is not well characterized. But this use case is not recommended and not likely to be used by a customer.

Thanks,

Michael

0 Oba 12 hours ago in reply to Michael Srinivasan

TI__Genius 17515 points

Hello Michael,

So do you mean the value on the table can apply for different divider case? In the customer case, it is CLKout0~2 and CLKout4~6?

Regards,
Oba

0 Michael Srinivasan 11 hours ago in reply to Oba

TI__Genius 10280 points

Oba-san,

Yes.

Thanks,

Michael

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LMK01801: Skew on between CG1 and CG2